1. Field of the Invention
The present invention relates to the field of liquid crystal display, and more particularly, to a voltage compensation circuit of a gate driver and a method of voltage compensation and a liquid crystal display device.
2. Description of the Prior Art
As shown in FIG. 1, a timing controller 12 controls source drivers 14 to drive data lines of a liquid crystal display (LCD) panel 13 in a conventional LCD device. Also, the timing controller 12 controls gate drivers 10 and 11 to drive scan lines of the LCD panel 13. A VGH voltage is a gate threshold voltage. The VGH voltage is inputted to the gate drivers 10 and 11 through a trace line. Afterwards, the gate drivers 10 and 11 conduct the VGH voltage to the LCD panel 13.
A resistor Rp1 and a resistor Rp2 are trace resistors between the gate drivers 10 and 11. Due to voltage loss of the line resistors when the VGH voltage is conducted through the trace line, a scan voltage conducted to the gate driver 10 is different from a scan voltage conducted to the gate driver 11. The voltage output by the gate driver 11 is smaller than the voltage output by the gate driver 10. The voltage output by the gate driver 11 becomes VGH-ΔV. When a narrow bezel is used in the LCD panel 13, the width of the trace line will become narrow. Besides, the cross-sectional area of the LCD panel 13 will decrease, and the resistance per unit length will increase. When the size of the LCD panel 13 increases, the trace line will become longer. Moreover, the resistance of the resistor Rp1 and the resistance of the resistor Rp2 will increase. According to the formula ΔV=IR, when R becomes larger, ΔV becomes larger as well. The voltage drop ΔV tends to cause mura for the LCD panel 13, which will affect display quality of the LCD panel 13.